[DOC] Example comparing spectral connectivity computed over time or over trials

CONTRIBUTING.md

@@ -44,7 +44,7 @@ Now you can finally run the tests by running `pytest` in the
 The documentation can be built using sphinx. For that, please additionally
 install the following:
 
-    $ pip install -r requirements_doc.text
+    $ pip install -r requirements_doc.txt
 
 To build the documentation locally, one can run:
 

doc/references.bib

@@ -238,4 +238,16 @@ @article{StamEtAl2012
   year={2012}, 
   month={Sep}, 
   pages={1415–1428}
+}
+
+ @article{KlimeschEtAl2004,
+  title = {Phase-locked alpha and theta oscillations generate the P1–N1 complex and are related to memory performance},
+  journal = {Cognitive Brain Research},
+  volume = {19},
+  number = {3},
+  pages = {302-316},
+  year = {2004},
+  issn = {0926-6410},
+  doi = {https://doi.org/10.1016/j.cogbrainres.2003.11.016},
+  author = {Wolfgang Klimesch and Bärbel Schack and Manuel Schabus and Michael Doppelmayr and Walter Gruber and Paul Sauseng}
 }